Naruto needs charge up time just to move too then XD
Interesting theory what you said about it being a spiritual chakra manifestation, we need a further explanation because some small things contradict themselves like the fact that Sasuke used once Amaterasu without bleeding during the war.
About Enton working that way I think it may be contradictory . Have a look at these (2) sentences from Narutopedia and link it with the first one I gave you. Unless you assume that Amaterasu needs look to be cast but manipulation (Enton) doesn't necessarily need direct sight